ADVANCES IN ACUTE STROKE IMAGING – OCT 2010 – KRISTINE BLACKHAM
For years, the working assumption has been that a mismatch between an MR perfusion deficit and diffusion lesion represents an estimate of ischemic penumbra. Several studies have shown that imaging is possible in acute stroke and have classified diffusionperfusion mismatch into broad categories, so as to demonstrate that certain categories may be more or less amenable to recanalization in terms of patient outcome. Imaging has broadened the field of acute stroke treatment, allowing practitioners to let go of the time restrictions that were a surrogate for irreversible brain damage and to improve the riskbenefit balance. The options for imaging have also broadened with the widespread availability of CT perfusion. Nevertheless, there are restrictions and limitations to both modalities which are areas of active research. I will summarize the imaging modalities that are in general use to date and their limitations, as well as the recent research that aims to overcome these limitations.
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